Scapy DHCP listener in Python
This script listens for DHCP Request and Discover packets on the LAN using scapy.
A little background on the DHCP protocol
Hosts issue a DHCP Discover packet to destination 255.255.255.255 to request an IP Address assignment from a DHCP server. DHCP Discover, Request, Offer, Ack and Inform packets are sent as broadcasts, all hosts on the LAN receive these packets. Because of the nature of the protocol, no special port mirroring or tapping is required on the host that runs this script.
This script is the foundation for creating a passive network discovery tool. We can collect and store the Mac Address, Hostname, and IP Address all hosts configured for DHCP IP address assignment.
